Medical waste processor and processing method

ABSTRACT

An apparatus for processing medical waste including: (i) a drum defining a substantially cylindrical treatment chamber having a closed end and an open end, wherein the drum is rotationally balanced about a rotational axis; (ii) an enclosing body supporting the drum so that the drum can be rotated within the body about the rotational axis of the drum, the body having an opening for accessing the open end of the drum; (iii) a movable barrier for selectively closing the opening for accessing the open end of the drum; (iv) a structure for supporting the enclosing body so that the pitch of the rotational axis of the drum is positioned or can be positioned in at least one position between about 0 degrees and about 30 degrees; and (v) a chemical generator for generating a germicidal agent operatively connected to introduce the germicidal agent into the enclosing body.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/306,696, filed Nov. 29, 2011, which is a continuation U.S. patentapplication Ser. No. 12/834,663, filed Jul. 12, 2010, which is acontinuation of U.S. patent application Ser. No. 11/639,084 filed Dec.14, 2006 entitled “MEDICAL WASTE PROCESSOR AND PROCESSING METHOD,” whichclaimed the benefit of U.S. Provisional Application No. 60/750,170 filedDec. 14, 2005.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable

REFERENCE TO MICROFICHE APPENDIX

Not applicable

TECHNICAL FIELD

The invention generally relates to the field of gathering, treating, anddisposing of potentially infectious medical waste.

SUMMARY OF THE INVENTION

According to a first aspect of the invention, an apparatus for treatingmedical waste, wherein the apparatus comprises: (i) a drum defining asubstantially cylindrical treatment chamber having a closed end and asubstantially open end, wherein the drum is rotationally balanced abouta rotational axis; (ii) an enclosing body supporting the drum so thatthe drum can be rotated within the body about the rotational axis of thedrum, the body having an opening for accessing the open end of the drum,wherein the opening is located substantially in a plane perpendicular tothe rotational axis of the drum; (iii) a movable barrier for selectivelyclosing the opening for accessing the open end of the drum; (iv) astructure for supporting the enclosing body so that the pitch of therotational axis of the drum is positioned or can be positioned in atleast one position between about 0 degrees and about 30 degrees; and (v)a chemical generator for generating a germicidal agent operativelyconnected to introduce the germicidal agent into the enclosing body

According to another aspect of the invention, an apparatus for treatingmedical waste is provided, wherein the apparatus comprises: (i) a drumdefining a substantially cylindrical treatment chamber having a closedend and a substantially open end, wherein the drum is rotationallybalanced about a rotational axis; (ii) an enclosing body supporting thedrum so that the drum can be rotated within the body about therotational axis of the drum, the body having an opening for accessingthe open end of the drum, wherein the opening is located substantiallyin a plane perpendicular to the rotational axis of the drum; (iii) amovable barrier for selectively closing the opening for accessing theopen end of the drum; (iv) a structure for supporting the enclosing bodyso that the pitch of the rotational axis of the drum is positioned orcan be positioned in at least one position between about 0 degrees andabout 30 degrees; and (v) a plurality of rotationally-balanced bladespositioned inside the drum, whereby when the drum is rotated, thetumbling of the medical waste in the treatment chamber onto the bladeshelps rupture containers and bags of the medical waste.

According to yet another aspect of the invention, a method of treatingmedical waste with an apparatus is provided, (A) wherein the apparatuscomprises: (i) a drum defining a substantially cylindrical treatmentchamber having a closed end and a substantially open end, wherein thedrum is rotationally balanced about a rotational axis; (ii) an enclosingbody supporting the drum so that the drum can be rotated within the bodyabout the rotational axis of the drum, the body having an opening foraccessing the open end of the drum, wherein the opening is locatedsubstantially in a plane perpendicular to the rotational axis of thedrum; (iii) a movable barrier for selectively closing the opening foraccessing the open end of the drum; (iv) a structure for supporting theenclosing body so that the pitch of the rotational axis of the drum ispositioned or can be positioned in at least one position between about 0degrees and about 30 degrees; and (iv) a movable mounting for theenclosing body operatively positioned between the enclosing body and thestructure for supporting the enclosing body such that the pitch of therotational axis of the drum can be selectively moved; and (B) whereinthe method comprises the steps of: (i) moving the enclosing body suchthat the pitch of the rotational axis of the drum is between about 10degrees and about 30 degrees and such that the opening is oriented atleast partially upward to facilitate loading of medical waste at leastpartially downward into the treatment chamber; (ii) loading medicalwaste through the opening into the treatment chamber; (iii) positioningthe movable barrier to close the opening; (iv) moving the enclosing bodysuch that pitch of the rotational axis of the drum is between about 0degrees and about 10 degrees; (v) introducing into the treatment chambera germicidal agent; and (vi) rotating the drum to agitate the medicalwaste with the germicidal agent.

According to yet another aspect of the invention, a method of treatingmedical waste is provided comprising the steps of: (i) positioning anenclosing body for a drum such that the pitch of the rotational axis ofthe drum is upward such that an opening in the enclosing body foraccessing the drum is oriented at least partially upward to facilitateloading of medical waste at least partially downward into the drum; (ii)loading medical waste through the opening downward into the drum; (iii)closing the opening in the enclosing body; (iv) positioning theenclosing body such that pitch of the rotational axis of the drum issubstantially horizontal relative to the upward position; (v) rotatingthe drum to agitate the medical waste with the germicidal agent; and(vi) introducing into the enclosing body a germicidal agent to beagitated with the medical waste in the drum. Preferably, this methodfurther comprising the steps of: (vii) re-opening the opening in theenclosing body; and (viii) positioning the enclosing body such that thepitch of the rotational axis of the drum is between about 10 and about30 degrees and such that the opening is oriented at least partiallydownward to facilitate unloading of medical waste at least partiallydownward from the drum; and (ix) unloading the treated medical wastefrom the drum. More preferably, a plurality of rotationally-balancedblades are positioned inside the drum, whereby when the drum is rotated,the tumbling of the medical waste in the treatment chamber onto theblades helps rupture containers and bags of the medical waste.

According to still another aspect of the invention, a method of treatingmedical waste is provided comprising the steps of: (i) positioning anenclosing body for a drum such that the pitch of the rotational axis ofthe drum is upward such that an opening in the enclosing body foraccessing the drum is oriented at least partially upward to facilitateloading of medical waste at least partially downward into the drum; (ii)loading medical waste through the opening downward into the drum; (iii)closing the opening in the enclosing body; (iv) positioning theenclosing body such that pitch of the rotational axis of the drum issubstantially horizontal relative to the upward position; and (v)rotating the drum to agitate the medical waste with the germicidalagent, wherein a plurality of rotationally-balanced blades arepositioned inside the drum, whereby when the drum is rotated, thetumbling of the medical waste in the treatment chamber onto the bladeshelps rupture containers and bags of the medical waste. Preferably, thismethod further includes the step of: (vi) introducing into the enclosingbody a germicidal agent to be agitated with the medical waste in thedrum.

It should be appreciated that the steps of the methods according to theinvention can be performed in any practical sequence. It is a generalobject of the present invention to provide improved apparatuses andmethods for treating medical waste. Other and further objects, featuresand advantages of the present invention will be readily apparent tothose skilled in the art when the following description of the preferredembodiments is read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present disclosure and advantagesthereof may be acquired by referring to the following description takenin conjunction with the accompanying drawings, which:

FIG. 1 is a perspective view of an apparatus according to apresently-preferred embodiment for treating medical waste, wherein theenclosing body of the apparatus (with the drum therein, not shown inthis figure) is shown in a substantially horizontal position forrotating the drum and agitating medical waste in the drum and whereinthe outer movable barrier is shown in a closed position.

FIG. 2 is a perspective view of the inside of the enclosure body of theapparatus shown in FIG. 1 showing a cut-away into the interiorprocessing chamber of the drum.

FIG. 3 is a perspective view of a presently-preferred embodiment of ablade for the interior of the drum.

FIG. 4 is a side view of the apparatus shown in FIG. 1, wherein theenclosing body (with the drum therein, not shown in this figure) isshown in a downwardly pitched position for unloading and wherein theouter movable barrier is shown in an open position.

FIG. 5 is a side view of the apparatus shown in FIG. 1, wherein theenclosing body (with the drum therein, not shown in this figure) isshown in a downwardly pitched position for unloading and wherein theouter movable barrier is shown in an open position.

FIG. 6 is a front view of the apparatus shown in FIG. 1, wherein theenclosing body (with the drum therein, not shown in this figure) isshown in a substantially horizontal position with an inner movablebarrier shown positioned to close the drum inside the enclosing body.

FIG. 7 is a detail of a presently-preferred embodiment of the innermovable barrier shown in FIG. 6, including four latches for attachingthe inner movable barrier to the drum (not shown in this figure).

FIG. 8 is a detail of a lower, rear of a portion of the apparatusshowing a plurality of fluid inlets and a drain line with a traptherein.

FIG. 9 is an exploded view of a trap with basket for the drain line ofthe apparatus according to a presently-preferred embodiment.

FIG. 10 is a block diagram of the components of an apparatus accordingto a presently-preferred embodiment.

DETAILED DESCRIPTION OF PRESENTLY PREFERRED EMBODIMENTS

As used herein and in the appended claims, the words “comprise,” “has,”and “include” and all grammatical variations thereof are each intendedto have an open, non-limiting meaning that does not exclude additionalelements or parts of an assembly, subassembly, or structural element.

As used herein, the term “medical waste” means and refers to any solidwaste that is generated in the diagnosis, treatment, or immunization ofhuman beings or animals, in research pertaining thereto, or in theproduction or testing of biologicals, including but not limited to:blood-soaked bandages; culture dishes and other glassware; discardedsurgical gloves, such as after surgery; discarded surgical instruments,such as scalpels; needles, such as used to give shots or draw blood;cultures, stocks, swabs used to inoculate cultures; lancets, such as thelittle blades the doctor pricks a finger with to get a drop of blood;sharps containers for used needles, syringe hubs, and syringes; plastictrash bags containing such medical waste; and linen that may beinfectious.

As used herein, the term “germicidal agent” means and refers to anychemical agent that is capable of significant germicidal action atstandard temperature and pressure (“STP”). A chemical agent for agermicidal purpose may be formed, activated, or accelerated by theaction of heat or radiation, but such heat or radiation is not otherwiserequired for the germicidal action by the chemical.

As used herein, the word “controller” means and refers to anymechanical, electrical, or electro-mechanical device, such as amechanical switch or variable controller, that controls the operation ofa mechanical function, for example, a motor direction, motor speed, orthe opening and closing of a valve.

If there is any conflict in the usages of a word or term in thisspecification and one or more patent or other documents that may beincorporated herein by reference, the definitions that are consistentwith this specification should be adopted.

Apparatus

Referring now to FIG. 1 and FIG. 2 of the drawing, according to a firstaspect of the invention, an apparatus for treating medical waste,wherein the apparatus 10 comprises: (i) a drum 12 defining asubstantially cylindrical treatment chamber 12 a having a closed end 12b and a substantially open end 12 c, wherein the drum 12 is rotationallybalanced about a rotational axis 12 d; (ii) an enclosing body 14supporting the drum 12 so that the drum can be rotated within the body14 about the rotational axis 12 d of the drum, the body 14 having anopening 14 a for accessing the open end 12 c of the drum, wherein theopening 14 a is located substantially in a plane perpendicular to therotational axis 12 d of the drum; (iii) a movable barrier 16 forselectively closing the opening 14 a for accessing the open end 12 c ofthe drum 12; (iv) a structure 18 for supporting the enclosing body 14 sothat the pitch of the rotational axis 12 d of the drum is positioned orcan be positioned in at least one position between about 0 degrees andabout 30 degrees.

As shown in FIG. 1, the support structure 18 preferably includes a base18 a, major support legs 18 a and 18 b. Preferably, the apparatus 10 cansupport the rotational axis 12 d of the drum 12 in at least asubstantially horizontal position, and more preferably the apparatus 10is adapted for pitching the axis 12 a of the drum 12. upwardly anddownwardly from the horizontal, as will hereinafter be described in moredetail.

Also as shown in FIG. 1, the apparatus 10 has a computer control panel21 with digital readout 21 a and an input keypad 21 b for controllingthe apparatus 10 and processes using the apparatus 10. As willhereinafter be described in more detail, the computer control panel 21can be used as a convenient user-interface for the various specificcontrollers of the apparatus and steps of the process according to theinvention. As will be appreciated, the computer control panel 21 can beoperatively connected to a remote computer or to the internet for remotemonitoring and control of the apparatus 10 and processes using theapparatus 10.

Motor for Rotating Drum

Continuing to refer to FIG. 1, the apparatus 10 has a motor 22operatively connected for rotating the drum 12. The motor 22 ispreferably operatively positioned on the enclosing body 14. The motor 22is preferably an electric motor. More preferably, the motor 22 is avariable speed motor.

Controller for Rotational Speed of Drum

Referring briefly to the block diagram of FIG. 10, the apparatus 10further comprises a controller 24 for the rotational speed of the drum12. The controller 24 is operatively connected to the motor 22. Thecontroller 24 for the rotational speed of the drum can selectivelycontrol the rotation of the drum at a rotational speed slower than fortumbling medical waste in the drum. According to preferred embodiments,the controller 24 for the rotational speed of the drum can selectivelycontrol the rotation of the drum 12 at a rotational speed for tumblingmedical waste in the drum. The controller 24 for the rotational speed ofthe drum can selectively control the rotation of the drum at arotational speed for centrifugally drawing fluid from medical waste inthe drum. As hereinafter described in more detail, the controller 24 ispreferably part of a computer control system for the apparatus 10. Thecontroller 24 is preferably operatively connected to and part of thecomputer control panel 21 shown in FIG. 1. In addition, the apparatuspreferably includes an emergency stop button 25 for the motor 22 to stopthe rotation of the drum if there is any major operational problem or inany kind of emergency. More preferably, the emergency stop button 25stops all functions of the apparatus 10.

Movable Mounting for Changing Pitch to Facilitate Loading of the Drum

Referring again to FIG. 1 of the drawing, according to a presentlypreferred embodiment, the apparatus 10 further comprises: a movablemounting for the enclosing body 14 operatively connected between thesupport structure 18 and the enclosing body 14, whereby the pitch of therotational axis 12 d of the drum 12 can be selectively moved. Accordingto a presently most preferred embodiment, the movable mounting includesat least two pivotal mountings 26 a and 26 b, which are preferablyaligned along a common pivotal axis lying in a substantially horizontalplane. The movable mounting preferably further includes another twopivotal mountings 26 c and 26 d, (where 26 d is not shown in FIG. 1because it is on the other side of the apparatus 10), which are alsopreferably aligned along a common pivotal axis lying in a substantiallyhorizontal plane. Preferably, at least one of the sets of pivotalmounts, either the set of pivotal mountings 26 a and 26 b or the set ofpivotal mountings 26 c and 26 d, are operatively connected to hydrauliccylinders 27 for adjusting the pitch of the enclosure body 14 and drumtherein. The hydraulic cylinders 27 also have pivotal mountings 28operatively positioned between the base 18 a of the support structure 18and the hydraulic cylinders 27, which allows the hydraulic cylinders 27to adjust their angle with the pitching of the apparatus 10.

As shown in FIG. 4, most preferably, the movable mountings 26 a and 26 band movable mountings 26 c and 26 d of the apparatus 10 allows theenclosing body 14 to be moved such that the pitch of the rotational axis12 d of the drum 12 is moved upward from a substantially horizontalposition. Preferably, the pitch can be adjusted to be upward betweenabout 10 degrees and about 30 degrees to the horizontal and such thatthe opening 14 a is oriented at least partially upward to facilitateloading of medical waste at least partially downward into the treatmentchamber 12 a. Most preferably, the pitch can be adjusted upward to about22 degrees to the horizontal.

Movable Mounting for Changing Pitch to Facilitate Unloading of the Drum

As shown in FIG. 5, most preferably the movable mounting 26 of theapparatus 10 allows the enclosing body 14 to be moved such that thepitch of the rotational axis 12 d of the drum 12 is moved downward froma substantially horizontal position. Preferably, the pitch can beadjusted to be downward between about 10 and about 30 degrees to thehorizontal and such that the opening 14 a is oriented at least partiallydownward to facilitate unloading of medical waste at least partiallydownward from the treatment chamber 12 a. Most preferably, the pitch canbe adjusted downward to about 22 degrees to the horizontal.

As shown in FIGS. 1, 4, and 5, the pitch of the rotational axis 12 d ofthe drum 12 in the enclosing apparatus 14 is preferably moved byhydraulic cylinders 27. As previously described in more detail, thehydraulic cylinders 27 are preferably operatively connected between theenclosing body 14 and the support structure 18. Referring briefly toFIG. 10, a controller 27 a for the hydraulic system 27 is operativelyconnected to the hydraulic system 27. As hereinafter described in moredetail, the controller 27 a is preferably part of a computer controlsystem for the apparatus 10. The controller 27 a is preferablyoperatively connected to and part of the computer control panel 21 shownin FIG. 1.

Controller for Slow Rotation of Drum for Loading/Unloading

Referring again to the block diagram of FIG. 10, according to apreferred embodiment of the invention, the controller 24 is capable ofcontrolling a very slow rotational speed of the drum 12. The controller24 is operatively connected to the motor 22. The controller 24 forpreferably can selectively control the rotation of the drum for lessthan a single rotation of the drum, whereby such rotation can facilitateloading or unloading of the drum 12. Most preferably, the controller 24for very slow rotational speed of the drum 12 provides for selectivelyrotating the drum in either rotational direction. Most preferably, thecontroller 24 for very slow rotational speed of the drum provides forvariable rotational speed. Further, most preferably, the controller 24for very slow rotational speed of the drum 12 comprises a manualcontroller. A purpose of such very slow rotation and rotation for lessthan a single rotation of the drum 12 is to allow for the automatedloading or unloading of the medical waste, with minimal risk of injuryto a human operator of the apparatus 10. As hereinafter described inmore detail, the controller 24 is preferably part of a computer controlsystem for the apparatus. The controller 24 is preferably operativelyconnected to and part of the computer control panel 21 shown in FIG. 1.

Outer Movable Barrier

Referring to FIG. 1, preferably, the outer movable barrier 16 is a doorhaving hinges 30. This allows for easy opening and closing of theopening 14 a of the enclosing body 14.

The movable barrier 16 is preferably moved on the hinges 30 by ahydraulic system 31. The hydraulic system 31 is preferably operativelyconnected between the enclosing body 14 and the movable barrier 16.Referring briefly to FIG. 10, a controller 31 a for the hydraulic system31 is operatively connected to the hydraulic system 31. As hereinafterdescribed in more detail, the controller 31 a is preferably part of acomputer control system for the apparatus 10. The controller 31 a ispreferably operatively connected to and part of the computer controlpanel 21 shown in FIG. 1.

The movable barrier 16 also preferably includes a latch system 33 forlatching the movable barrier 16 shut. Referring to FIG. 6, the latchsystem 33 can include, for example, a latching arm 33 a and a receivingbody 33 b. More preferably, the latch 33 is hydraulically operated,which hydraulic operation can be part of the hydraulic system 31 for theoperation of the movable barrier 16.

Continuing to refer to FIG. 1, preferably, the movable barrier 16further comprises a transparent window 32 for viewing inside theenclosure body toward the treatment chamber 12 a when the movablebarrier 16 is in a closed position for the opening 14 a.

Inner Movable Barrier for Drum

Referring now to FIGS. 6 and 7, the apparatus 10 preferably furthercomprises: an inner movable barrier 34 for selectively closing the openend 12 c of the drum 12, thereby preventing any substantial solids ofmedical waste from escaping from the treatment chamber 12 a duringrotation of the drum into enclosing body 14 outside drum 12.

According to a presently most preferred embodiment of the invention, theinner movable barrier 34 for the drum 12 comprises a latching system 35for selectively attaching the inner movable barrier 34 to the drum. Forexample, the latching system 35 can comprise a plurality of latchassemblies 35 a, adjacent the periphery 34 a of the inner movablebarrier 34, wherein each of the latches 35 a has a pin 35 b, and acorresponding plurality of apertures 35 c (shown in FIG. 2) in theperiphery of the open end 12 c of the drum 12. Thus, the inner movablebarrier 34 can be positioned adjacent the open end 12 c of the drum andthe pins 35 b can be moved into latching engagements with the pluralityof apertures 35 c in the periphery of the open end 12 c of the drum. Theinner barrier 34 can be removed from the open end 12 c of the drum bypulling the pins 35 b out of engagement with the plurality of apertures35 c. Each of the pins 35 b preferably includes a locking end 35 d thatcan be locked into a cradle 35 e and biased into the locked cradle witha spring 35 f in a pin holding body 35 g attached to the inner movablebarrier.

Most preferably, the inner movable barrier 34 further comprises an innertransparent window 36 for viewing inside of the treatment chamber 12 aof the drum.

Blades in Drum

Referring now to FIGS. 2 and 3 of the drawing, the apparatus 10preferably comprises: a plurality of rotationally-balanced blades 38positioned inside the drum 12, whereby when the drum is rotated, thetumbling of the medical waste in the treatment chamber 12 a onto theblades 38 ruptures containers and bags of the medical waste. Preferably,the blades 38 are positioned on an inside wall of the drum 12.Preferably, the blades 38 are adapted to rupture disposal containers forneedles or syringes that may be present in the medical waste when thedrum 12 rotates at a speed to tumble the medical waste in the treatmentchamber 12 a. The preferred arrangement of the blades is a segmenteddesign to insure that all the waste material is broken open to allowboth the liquid and/or gas to penetrate all parts of the waste load tofacilitate the kill. The blades 38 are preferably positioned along theentire length of the drum 12. If desired, additional blades (not shown)can be placed adjacent the closed end of the drum to provide additionalrupturing, penetration, and breaking of the medical waste as it istumbled in the drum. This can be especially helpful, for example, if thedrum is pitched backward a few degrees during tumbling of the medicalwaste when agitating it with a germicidal agent, which reduces theamount of the medical waste tumbling against the movable barrier 16.

FIG. 3 in particular illustrates a preferred embodiment of a blade 38for use in the invention. The blade 38 preferably is formed of stainlesssteel or similarly strong material that is also resistant to chemicalcorrosion. The blade 38 is preferably in the form of an elongated bodyhaving a blade portion 38 a and flange portions 38 b and 38 c. Theflange portions 38 b and 38 c preferably have a plurality of apertures38 d therein. The apertures in the flange portions of the blade 38 canbe used for removably securing the blade 38 to the interior body of thedrum or a support structure 12 e of the drum 12, as shown in FIG. 2.

Continuing to refer to FIG. 3, the blade portion 38 a preferably hassubstantially sharpened edges 38 e. Further, the blade portion 38 a ispreferably segmented, which provides additional sharp corner edges 38 f.The sharp corner edges 38 f are believed to be particularly helpful inrupturing items commonly present in medical waste.

Drum Holes in Drum

Referring again to FIG. 2, preferably, at least a portion of the drum 12has a plurality of drum holes 40 adapted to allow the passage of fluidwhile retaining solid medical waste material therein. More preferably,the size and shape of the drum holes 40 in the drum 12 are adapted toprevent passage of whole needles and hubs of the sizes and types thatare most commonly in medical waste. For example, preferable the drumholes 40 are circular and the diameter of each of the drum holes 40 isless than or equal to 0.25 inches.

Fluid-Tight Enclosing Body

Referring to FIG. 6, according to a further aspect of the invention, theenclosing body 14 is fluid-tight, the movable barrier 16 is fluid-tight,and the apparatus 10 further comprises: a fluid-tight seal 42operatively positioned between the enclosing body 14 and the removablebarrier 16, whereby the enclosing body 14 is fluid tight when themovable barrier 16 closes the opening 14 a for accessing the open end 12c of the drum 12. More preferably, when the removable barrier 16 closesthe opening 14 a of the enclosing body 14 (and any other inlets, vents,drain lines, or other ports in the enclosing body 14 are also closed)the enclosing body 14 is fluid tight up to at least 25 pounds per squareinch (“psi”) above standard atmospheric pressure. More preferably, theenclosing body 14 is fluid tight up to about 100 psi above standardatmospheric pressure. Preferably, all the materials, seals, and valves,etc. of the apparatus that are expected to be routinely exposed to thegermicidal agent during operation of the apparatus 10 are selected to beresistant to chemical corrosion. For example, most preferably, thefluid-tight seal 42 is a Viton® material, which is highly resistant tochemical corrosion.

Fluid Inlet

Referring again to FIGS. 1 and 10, in the preferred example of theapparatus 10 having a fluid-tight enclosing body 14, the apparatus 10further comprises: at least one fluid inlet for delivering a treatmentfluid into the enclosing body. It is to be understood, of course, thatthe apparatus 10 can have a single fluid inlet or that the function orfunctions of the fluid inlet can be served by a plurality of fluidinlets, such as fluid inlets 44 a, 44 b, 44 c, and 44 d, as hereinafterdescribed in more detail, which can be plumbed in a variety ofconfigurations. Preferably, the apparatus 10 further comprises: at leastone fluid inlet valve, as hereinafter described in more detail, so thatthe fluid inlet or inlets 44 a-d can be selectively opened or closed,whereby the treatment fluid can be selectively introduced into theenclosing body 14. In addition, the apparatus 10 preferably furthercomprises: at least one controller, as hereinafter described in moredetail, for the fluid inlet valve or valves. As hereinafter described inmore detail, the controller is preferably part of a computer controlsystem for the apparatus.

Fluid Inlet to Germicidal-Agent Source

Referring to FIG. 10, according to a preferred embodiment, the fluidinlet 44 a is adapted to be connected to a germicidal-agent source 46,whereby the treatment fluid can comprise the germicidal agent. Thegermicidal-agent source 46 can be a supply tank (not shown) for thegermicidal agent. Preferably, the apparatus includes a germicidal agentline valve 46 a to the inlet 44 a so that the germicidal-agent source 46to the fluid inlet 44 a can be selectively opened or closed. Theapparatus 10 also preferably further comprises: a controller 46 b forthe germicidal agent line valve. As hereinafter described in moredetail, the controller 46 b is preferably part of a computer controlsystem for the apparatus. The controller 46 b is preferably operativelyconnected to and part of the computer control panel 21 shown in FIG. 1.

Germicidal Agent Generator

Continuing to refer to FIG. 10, more preferably than a supply tank forgermicidal agent, however, the germicidal agent 46 source of theapparatus 10 comprises: a chemical generator for generating thegermicidal agent, wherein the chemical generator is operativelyconnected to the controller for introducing the germicidal agent. Mostpreferably, the chemical generator is a chlorine dioxide generator andthe germicidal agent is chlorine dioxide.

Fluid Inlet to Water Source

Preferably, the fluid inlet 44 b is adapted to be connected to a watersource 48, whereby the treatment fluid can optionally comprise water.The water source can be connected to a city water supply, for example.Preferably, the apparatus 10 includes a water line valve 48 a to thefluid inlet 44 b so that the water source 48 to the fluid inlet 44 b canbe selectively opened or closed. The apparatus 10 also preferablyfurther comprises: a controller 48 b for the germicidal agent linevalve. As hereinafter described in more detail, the controller 48 b ispreferably part of a computer control system for the apparatus. Thecontroller 48 b is preferably operatively connected to and part of thecomputer control panel 21 shown in FIG. 1.

Fluid Inlet to Superheated Water or Steam Source

Preferably, the fluid inlet 44 c is adapted to be connected to asuperheated water or steam source 50, whereby the treatment fluid canoptionally comprise superheated water or steam. Preferably, theapparatus 10 includes a steam line valve 50 a to the fluid inlet 44 c sothat the steam source 50 to the fluid inlet 44 c can be selectivelyopened or closed. The apparatus 10 also preferably further comprises: acontroller 50 b for the steam line valve 50 a. More preferably, thecontroller 50 b introduces at least sufficient superheated water orsteam from the steam source 50 into the treatment chamber 12 a tosubstantially increase the temperature within the treatment chamber,whereby the sufficient time to achieve “Level IV Microbial Inactivation”is substantially shortened relative to ambient temperature. Ashereinafter described in more detail, the controller 50 b is preferablypart of a computer control system for the apparatus. The controller 50 bis preferably operatively connected to and part of the computer controlpanel 21 shown in FIG. 1.

Steam Generator

Preferably, the apparatus 10 further comprises: a steam generator forthe steam source 50.

Temperature Sensor

Continuing to refer to FIG. 10. the apparatus 10 preferably furthercomprises: a temperature sensor 52 operatively connected for determiningthe temperature of a treatment fluid inside the treatment chamber 12 a.The temperature sensor 52 can be operatively connected to a temperaturereadout visible to the operator of the apparatus 10, and more preferablyto a computer control system for the apparatus 10, which is hereinafterdescribed in more detail. The temperature sensor 52 is preferablyoperatively connected to the computer control panel 21 shown in FIG. 1.For example, the temperature readout can be part of the information thatcan be displayed in the digital readout 21 a.

Chemical Analyzer for Germicidal Agent

Continuing to refer to FIG. 10, preferably the apparatus 10 furthercomprises: a chemical analyzer 54 for the germicidal agent operativelyconnected to the controller for the introduction of the germicidal agentinto the treatment chamber. Preferably, the chemical analyzer 54 isconnected for determining the germicidal agent concentration of atreatment fluid in the treatment chamber 12 a, either by direct samplingfrom the treatment chamber or by indirect sampling of the treatmentfluid drawn from the treatment chamber. The chemical analyzer 54 can beoperatively connected to determine the concentration of a source oftreatment fluid or a portion of a fluid used for the treatment fluid,for example, the germicidal-agent source 46 or a recycled treatmentfluid that may have some germicidal agent concentration remainingtherein. With the data from the chemical analyzer, the controller forthe introduction of the germicidal agent into the treatment chamber canbalance the streams, for example, from the germicidal-agent source 46and a water source 48, superheated water or steam source 50, or arecycled treatment fluid source (as hereinafter described in moredetail), to achieve a desired concentration of the germicidal agent in atreatment fluid introduced into the treatment chamber 12 a. Ashereinafter described in more detail, the controller is preferably partof a computer control system for the apparatus. The chemical analyzer 54is preferably operatively connected to the computer control panel 21shown in FIG. 1.

Neutralizing Agent Source

Continuing to refer to FIG. 10, the apparatus 10 preferably furthercomprises: a controller for introducing a neutralizing agent for thegermicidal agent into the treatment chamber 12 a. The fluid inlet 44 dis adapted to be connected to a neutralizing agent source 58 forneutralizing the germicidal agent, whereby the germicidal agent canoptionally be at least partially neutralized prior to discharge of thegermicidal agent from the treatment chamber 12 a. The apparatus 10further comprises: a neutralizer line valve 58 a to the fluid inlet 44 dso that the neutralizing agent source 58 to the fluid inlet 44 d can beselectively opened or closed. In addition, the apparatus 10 furthercomprises: a controller 58 b for the neutralizing line valve. Ashereinafter described in more detail, the controller 58 b is preferablypart of a computer control system for the apparatus. The controller 58 bis preferably adapted for adjusting the amount or concentration ofneutralizing agent to accomplish the desired degree of neutralization ofthe germicidal agent expected to be or measured to be in the treatmentchamber of the apparatus.

Vent and Scrubber

The apparatus 10 preferably further comprises: a vent 60 to theatmosphere. The apparatus further comprises: a valve 60 a for the vent60, whereby the enclosing body 14 can be selectively vented or preventedfrom venting to the atmosphere. In this embodiment, the apparatus 10preferably further comprises: a controller 60 b for the valve 60 a forthe vent 60. As hereinafter described in more detail, the controller 60b is preferably part of a computer control system for the apparatus. Thecontroller 60 b is preferably operatively connected to and part of thecomputer control panel 21 shown in FIG. 1.

A scrubber (not shown) operatively in line with the vent 60 ispreferably added which utilizes the neutralization solution for a bubblethrough process to neutralize any fugitive gas, and a HEPA filter willtop off the scrubber to further reduce any possible release toatmosphere of the treated or untreated aerosols. The neutralizationsolution will be refreshed with each load, as it will be used toneutralize the active solution in the normal batch process. The scrubberacts to neutralize any fugitive gas emissions, and the HEPA filterremoves any organic aerosols that should be released from the drum. Aswitch is activated by the controller that calls for the neutralizationsolution to be added.

Drain Line

Preferably, the apparatus 10 further comprises: a drain line 62 from theenclosing body 14 for draining liquid from the enclosing body. It is tobe understood, of course, that the apparatus 10 can have a single drainline 62 or that the function or functions of the drain line 62 can beserved by a plurality of drain lines, which can be plumbed in a varietyof configurations. The apparatus 10 further comprises: a drain valve 62a for the drain line 62, whereby the liquid can be selectively containedor drained from the enclosing body 14. The apparatus further comprises:a controller 62 b for the drain valve 62 a. As hereinafter described inmore detail, the controller 62 b is preferably part of a computercontrol system for the apparatus. The controller 62 b is preferablyoperatively connected to and part of the computer control panel 21 shownin FIG. 1.

Trap in Drain Line

Referring to FIG. 8, the apparatus 10 preferably further comprises: atrap 64 in the drain line 62 for any needles and other debris from themedical waste that may escape the treatment chamber 12 a, whereby suchdebris is prevented from escaping downstream of the trap 64, forexample, into a sewage line 65 to sewage disposal.

Referring now to FIG. 9, the trap 64 in the drain line 62 preferablyfurther comprises a trap body portion 64 a and a removable cover 64 bfor accessing a removable basket 64 c positioned in the trap bodyportion 64 a, the basket having drain holes 64 d, whereby the basket 64c can be manually removed from the trap body portion 64 a to remove ordump the solid contents in the basket 64 b. The size and shape of thedrain holes 64 d in the removable basket 64 c are adapted to preventpassage of smaller sizes of medical waste than the drain holes 40 in thedrum 12.

The trap body 64 a is adapted to be operatively connected to the drainline 62 with a trap inlet 64 e. The trap body 64 a is adapted to beoperatively connected to a sewage line 65 with a trap outlet 64 f.

The trap body preferably has lid latches 64 g for keeping the lid closedon the trap body. The lid preferably includes a trap handle 64 h.

Liquid Holding Tank

Referring to FIG. 10, according to a preferred embodiment, the apparatus10 further comprises: a liquid holding tank 66 operatively connected tothe drain line 62 from the enclosing body 14. Preferably, the liquidholding tank 66 is fluid-tight, which helps control the escape ofgermicidal agent or other fumes into the surrounding atmosphere.

Recycling Line for Liquid Holding Tank

For the liquid holding tank 66 for spent treatment fluid, the apparatus10 further comprises: a tank drain line 68 from the holding tank 66 fordraining liquid in the holding tank to sewage disposal, and a recyclingline 70 from the holding tank 66 for directing liquid in the holdingtank into the enclosing body 14. The apparatus further comprises: a tankdrain valve 68 a for the tank drain line 68 and a recycling line valve70 a for the recycling line 70, whereby liquid can be selectivelycontained or drained from the holding tank 66 through the tank drainline 68, and preferably through the drain line trap 64 to the sewageline 65 for sewage disposal or selectively directed into the enclosingbody 14. The apparatus further comprises: a controller 68 b for the tankdrain valve; and a controller 70 b for the recycling line valve. Ashereinafter described in more detail, each of the controllers 68 b and70 b is preferably part of a computer control system for the apparatus.The controllers 68 b and 70 b are preferably operatively connected toand part of the computer control panel 21 shown in FIG. 1.

Chemical Analyzer for Germicidal agent from Recycling Line

Again referring to FIG. 10, for an apparatus 10 connected to orcomprising a liquid holding tank 66 for used treatment fluid, theapparatus preferably further comprises: a chemical analyzer, mostpreferably chemical analyzer 54, for determining the concentration ofthe germicidal agent in a liquid from the holding tank. It is to beunderstood, of course, that the chemical analyzer 54 can be operativelyconnected to sample fluids from various sources or that a plurality ofchemical analyzers can be employed, for example, a single analyzer foreach source desired to be analyzed for germicidal agent or otherchemical property. The apparatus 10 preferably further comprises: acontroller 72 for the ratio of fluids from the holding tank 66 and thegermicidal-agent source 46 to achieve a desired concentration ofgermicidal agent for use as a treatment fluid to be introduced into thetreatment chamber 12 a. As hereinafter described in more detail, thecontroller 72 is preferably part of a computer control system for theapparatus. The controller 72 is preferably operatively connected to andpart of the computer control panel 21 shown in FIG. 1.

Computer Control

The apparatus 10 preferably further comprises: a computer control system74 for at least the controller for the introduction of germicidal agent.Most preferably, the computer control system is operatively connected tobe the central controller for all the selectively operable elements ofthe apparatus 10. Preferably, the computer controller is operativelyconnected to a plurality of sensors on the apparatus for detecting therelevant operating state of the apparatus for each controller that isselectively operable. Preferably, the computer control system isoperatively connected to the Internet for remote access andcommunication with the computer controller.

Method of Treating Medical Waste

According to yet another aspect of the invention, a method of treatingmedical waste with an apparatus is provided, (A) wherein the apparatuscomprises: (i) a drum 12 defining a substantially cylindrical treatmentchamber 12 a having a closed end 12 b and a substantially open end 12 c,wherein the drum 12 is rotationally balanced about a rotational axis 12d; (ii) an enclosing body 14 supporting the drum 12 so that the drum canbe rotated within the body 14 about the rotational axis 12 d of thedrum, the body 14 having an opening 14 a for accessing the open end 12 cof the drum 12, wherein the opening 14 a is located substantially in aplane perpendicular to the rotational axis 12 a of the drum; (iii) amovable barrier 16 for selectively closing the opening 14 a foraccessing the open end 12 c of the drum 12; (iv) a structure 18 forsupporting the enclosing body 14 so that the pitch of the rotationalaxis 12 a of the drum 12 is positioned or can be positioned in at leastone position between about 0 degrees and about 30 degrees; and (iv) amovable mounting 26 for the enclosing body 14 operatively positionedbetween the enclosing body 14 and the structure 18 for supporting theenclosing body 14 such that the pitch of the rotational axis 12 d of thedrum 12 can be selectively moved; and (B) wherein the method comprisesthe steps of: (i) moving the enclosing body 14 such that the pitch ofthe rotational axis 12 d of the drum is between about 10 degrees andabout 30 degrees and such that the opening 14 a is oriented at leastpartially upward to facilitate loading of medical waste at leastpartially downward into the treatment chamber 12 a; (ii) loading medicalwaste through the opening 14 a into the treatment chamber 12 a; (iii)positioning the movable barrier 16 to close the opening 14 a; (iv)moving the enclosing body 14 such that pitch of the rotational axis 12 dof the drum is between about 0 degrees and about 30 degrees; (v)introducing into the treatment chamber 12 a a germicidal agent; and (vi)rotating the drum 12 to agitate the medical waste with the germicidalagent.

Moving Body on Movable Mounting to Change Pitch for Loading

The step of loading medical waste into the treatment chamber 12 apreferably further comprises: pouring the medical waste from a bin (notshown) through the upwardly oriented opening 14 a for accessing the openend 12 c of the drum 12 and into the treatment chamber 12 a. The step ofloading preferably further comprises: rotating the drum 12 about therotational axis 12 d of the drum so that the treated medical waste isrotated upward on an inner wall of the drum 12 and then tumbles bygravity farther down into the treatment chamber 12 a of the drum. Thestep of loading preferably further comprises: rotating the drum 12 atleast one-half of a revolution about the rotational axis 12 d in onerotational direction and rotating the drum at least one-half arevolution about the rotational axis 12 d in the opposite rotationaldirection.

The step of moving the enclosing body 14 such that the pitch of therotational axis 12 d of the drum 12 is between about 0 degrees and about30 degrees further comprises: moving the enclosing body 14 such that thepitch of the rotational axis 12 d of the drum 12 is substantially 0degrees to a horizontal plane. It is believed that this positionprovides maximum benefit of tumbling the medical waste with thegermicidal agent in the treatment chamber 12 a. However, as discussedabove, it is expected that it can be helpful to tumble the medical wastein the drum when the rotational axis 12 d of the drum 12 is pitchedslightly upward (backward) a few degrees from the horizontal, whichhelps keep the medical waste tumbling slightly toward the rear, closedend of the drum 12 b. For example, it is presently believed that therotational axis 12 d of the drum 12 can be advantageously positioned atabout 5 degrees from the horizontal plane with the front, open end 12 cof the drum oriented slightly upward.

Moving the Movable Mounting to Change Pitch for Unloading

The method preferably further comprises the steps of: (vii) moving themovable barrier 16 to reopen the opening 14 a; and (viii) moving theenclosing body 14 such that the pitch of the rotational axis 12 d of thedrum 12 is between about 10 and about 30 degrees and such that theopening 14 a is oriented at least partially downward to facilitateunloading of medical waste at least partially downward from thetreatment chamber 12 a; and (ix) unloading the treated medical wastefrom the treatment chamber 12 a. Preferably, the step of unloadingfurther comprises: rotating the drum 12 about the rotational axis 12 dof the drum so that the treated medical waste is rotated upward on aninner wall of the drum 12 and then tumbles by gravity out of the openend 12 c of the treatment chamber 12 a of the drum and to the outside ofa lower edge of the opening 14 a in the enclosing body 14. Preferably,the step of unloading further comprises: rotating the drum 12 at leastone-half of a revolution about the rotational axis 12 d in onerotational direction and rotating the drum at least one-half arevolution about the rotational axis in the opposite rotationaldirection.

Collecting Medical Waste & Disposing of Disinfected Medical Waste

The method preferably further comprises the step of: collecting themedical waste into a bin for transport to the apparatus 10. The methodpreferably also further comprises the step of: unloading the medicalwaste that has been treated in the apparatus 10 into a bin for transportto a non-medical waste collection area for disposal as non-medicalwaste.

Method with Blades Positioned in Drum

Preferably, the apparatus 10 employed in the method further comprises: aplurality of rotationally-balanced blades 38 positioned inside the drum12, whereby during the step of rotating the drum to agitate the medicalwaste with the germicidal agent, the tumbling of the medical waste inthe treatment chamber 12 a onto the blades 38 ruptures containers andbags of the medical waste. This helps expose the interiors of suchcontainers and bags to the germicidal agent. Preferably, the blades 38are positioned on an inside wall of the drum 12. Preferably, the blades38 are adapted to rupture disposal containers for needles or syringesthat may be present in the medical waste when the drum 12 rotates at aspeed to tumble the medical waste in the treatment chamber 12 a.

Fluid-Tight Enclosing Body for Apparatus in Method

Preferably, the enclosing body 14 of the apparatus 10 employed in themethod is fluid-tight, the movable barrier 16 is fluid-tight, and theapparatus further comprises: a fluid-tight seal 42 operativelypositioned between the enclosing body 14 and the removable barrier 16,whereby the enclosing body 14 is fluid tight when the movable barrier 16closes the opening 14 a for accessing the open end 12 c of the drum 12.

Closing Vent while Germicidal Agent is in Treatment Chamber

In a preferred embodiment wherein the enclosing body 14 is fluid tight,the apparatus 10 employed in the method preferably further comprises: avent 60 to the atmosphere. The apparatus further comprises: a valve 60 afor the vent 60, whereby the enclosing body 14 can be selectively ventedor prevented from venting to the atmosphere. In this embodiment, theapparatus 10 preferably further comprises: a controller 60 b for thevalve 60 a for the vent 60. In a preferred embodiment of the method withsuch a preferred embodiment of the apparatus 10, the vent 60 is closedwhile germicidal agent is introduced into the treatment chamber 12 a.

Introducing Germicidal Agent

The step of introducing into the treatment chamber 12 a a germicidalagent preferably further comprises the step of: introducing a germicidalagent having at least a sufficient effectiveness in at least asufficient concentration under conditions at least sufficient to achieve“Log 6 Kill.” According to the presently most-preferred embodiment, thegermicidal agent comprises chlorine dioxide.

Heating—e.g., with Superheated Water or Steam

The method preferably further comprises the step of: heating the medicalwaste in the treatment chamber. The step of heating the medical wastecan further comprise, for example: introducing superheated water orsteam into the treatment chamber 12 a.

Neutralizing Agent for Germicidal Agent

The method preferably further comprising the step of: after the step ofagitating the medical waste with the germicidal agent in the treatmentchamber 12 a; neutralizing any residual germicidal agent. Where thegermicidal agent comprises chlorine dioxide, the neutralizing agentcomprises a sulfite. More preferably, the neutralizing agent comprises awater-soluble inorganic sulfite salt, such as sodium or potassiumsulfite.

Recycling Germicidal Agent

According to a presently preferred embodiment, the method furthercomprises the step of: recycling the germicidal agent for use in asubsequent treatment of another batch of medical waste.

Example Machine and Method

A medical waste processor and processing method has been designed anddeveloped as an on-site alternative for healthcare facilities by OncoreTechnologies, LLC located in Grand Prairie, Tex. The processor andmethod is designed for use by any hospital facility or consortium ofarea healthcare facilities.

The processor and method treat infectious medical waste by subjectingsuch waste to a liquid germicidal solution in a liquid-tight chamber.Steam may also be used to activate or accelerate the process. Thechamber is mechanically moved or rotated to create a turbulence thatmechanically agitates the infectious waste with the germicide solution.

Preferably, the movement or rotation of the chamber macerates theinfectious medical wastes using cutting blades mounted on the interiorof the rotating chamber. More preferably but not necessarily, thecutting blades are positioned to be in opposing relation to help moreeffectively macerate the infection medical wastes. The blades areadapted to rupture bags and containers of medical waste or that aretypically included in medical waste.

After mechanically agitating the infectious medical waste with theliquid germicidal solution in the chamber under sufficient conditions ofconcentration of the germicidal agent or agents in the liquid germicidalsolution, possibly using steam or heat to accelerate the germicidalaction, mechanical agitation, and agitation time necessary forgermicidal contact to convert the infection medical waste into anoninfectious waste, the Unit neutralizes or inactivates the germicidalsolution.

In addition, the processor and method preferably includes separating theliquids from the solid waste materials to convert infectious medicalwaste into a noninfectious waste. Preferably, the liquids are separatedfrom the solid waste materials after the liquid germicidal solution hasbeen neutralized or inactivated.

An example of such a medical waste processor, which is also capable ofbeing used in the medical waste processing method, is based on a washingapparatus that has been modified for the purposes of this invention,including with the addition of (1) a germicidal solution generator, (2)opposing cutting blades in the chamber, and (3) a controller thatregulates germicidal addition and all cycle processes. An example of asuitable washing apparatus for use in the present invention is theFLPS-1200 Tilt End-Loading Apparatus, which is commercially availablefrom Washex, Inc. In this example, the “Unit” has a capacity ofprocessing approximately 275 of medical waste per cycle. Atapproximately 20 minutes per cycle, it has a capacity of approximately500-750 pounds per hour. A larger Unit is currently capable of treatingapproximately 450 pounds per cycle. Future models will have the capacityto treat from 100 to 500 pounds per cycle. A smaller waste-volumeprocessing model is envisioned for the future to meet the needs of thesmaller hospital or large clinic.

The Unit most preferably utilizes chlorine dioxide to inactivatemicrobial organisms. The Unit successfully inactivates challengemicroorganisms representing vegetative bacteria (Staphylococcus aureus),viruses (attenuated Poliovirus 2), fungi (Candida albicans), protozoa(Giardia cysts), Mycobacteria (M. bovis), and bacterial endospores (B.stearothermophilus).

Level of Treatment

As summarized in Table I, treatment efficacy studies conducted on theUnit utilized bacterial spores from Bacillus stearothermophilus. It iswell established that in the hierarchy of microbial resistance,bacterial endospores exhibit the greatest degree of resistance to bothheat and chemical biocides than do vegetative bacteria, viruses, fungi,and protozoa. This difference in degree of resistance is often orders ofmagnitude with variables dependent on the organism and the chemical orthermal agent to which the organism is subjected. Four microbialinactivation levels have been defined by both State and TerritorialAssociation on Alternate Treatment Technologies (STA²T²) in theTechnical Assistance Manual: State Regulatory Oversight of Medical WasteTreatment Technologies (1999) and in Guidance for Evaluating MedicalWaste Treatment Technologies (USEPA, 1993). Both these documents defineLevel IV Microbial Inactivation as having the ability to inactivate 10⁶bacterial spores. Although B. subtilis spores are typically used as thechemical resistance standard, spores from B. stearothermophilus providean equivalent measure of resistance to chemical inactivation and eitheris recommended to verify Level IV microbial inactivation. In this studyB. stearothermophilus spores were used to demonstrate microbialeffectiveness of the Unit. Use of B. stearothermophilus spores isrequired in performing these tests on the Unit since the spores arethermophilic and require temperatures of 55-61° C. to germinate to avegetative state. Incubation at these temperatures precludes the growthof common contaminants that might be introduced to the spore stripsduring the neutralization cycle that follows the chlorine dioxidetreatment cycle.

TABLE I Summary of Treatment Efficacy Log Reduction Achieved LogReduction Microorganism (Test Average) Required B. stearothermophilusspores 6.6* 6.0 *Limited by the initial spore concentration on the sporestrips

Characterization of the Proposed Treatment Process

The Unit is a chemical inactivation medical waste treatment technologyutilizing chlorine dioxide to inactivate microorganisms. Combinedphysical turbulent agitation and internal cutting blades provide themechanisms to break open closed sharps containers and to saturatemedical wastes with chlorine dioxide solution during the treatmentprocess. Through a pre-programmed controller, the unit sequences toautomatically:

-   -   1) Load medical waste into the treatment chamber;    -   2) Close and seal the door to the treatment chamber;    -   3) Generate chlorine dioxide solution to the proper        concentration;    -   4) Fill the chamber with the prescribed concentration and amount        of chlorine dioxide solution, and steam, if desired to        accelerate the treatment process;    -   5) Initiate and complete the processing cycle;    -   6) Initiate and complete a chlorine dioxide neutralization        cycle;    -   7) Discharge neutralized processing solution; and    -   8) Open the treatment chamber door and automatically discharge        treated medical waste residue.

Waste Compatibility with Proposed Treatment Process

Medical waste treatment efficacy studies were conducted using acomposite simulated medical waste stream that was comprised, by weight,of: The simulated load was comprised, by weight, of: 5% organic material(protein supplement), 27% cellulose, 31% non-woven plastics, 7% liquids,and 11% hard plastics. Previously decontaminated (steam sterilized)sharps containers (19%) were also placed into the waste stream todetermine the efficiency of their physical treatment by the process. Theprotein supplement was added to simulate a five percent bovine bloodcontent that would typify the organic load in a medical waste streamoriginating from blood, body fluids, diagnostic tissue samples, andlaboratory cultures and growth support mediums. The plastic andcellulose simulated waste components representative of medical wasteitems consisted of woven plastics (e.g., drape and gown materials), hardplastics (e.g., materials made of polyethylene, polypropylene, orpolystyrene), and cellulose (e.g., paper towels, cotton chucks, etc.).No attempt was made in the studies conducted to ascertain theeffectiveness of the Unit against singular high-organic waste streamssuch as animal carcasses, their body parts, bulk whole blood, and animalbedding. It is known that chlorine dioxide reacts with organic materialto deplete the initial chlorine dioxide concentration as a result ofthat interaction. From the data collected evaluating residual chlorinedioxide concentration in the effluent after treating the waste (beforeneutralization), the organic load never exceeded the lowering of theinitial concentration of chlorine dioxide by more than 15% under 5%organic load conditions.

It is known that chlorine dioxide is only affected by organic materialsand that the addition of organic material (primarily the proteinsupplement) was the only challenge that the waste load compositionpresented. Plastics, glass, and metals have no affect on the microbialinactivation effectiveness of chlorine dioxide. Since this system adds aliquid (the germicide solution), liquids also present no limitation tothe technology.

Density and compaction of the waste stream also present no limitationsince the unit provides a high degree of turbulent agitation duringtreatment. In combination with the cutting blades and turbulent waterforces that are generated during waste processing, even closed andsealed sharps containers are broken open and contents scattered.

The amount of organic materials in the medical waste stream has thepotential to influence the chlorine dioxide concentration in thetreatment solution. As previously noted, the Unit has been designed anddemonstrated to effectively treat a composite medical waste streamconsisting of bulk blood, blood products, body fluids, microbiologicalwastes, sharps waste, and isolation wastes. Primary waste loads of highorganic-containing wastes from animals including bedding and carcasseshave not been tested to determine treatment conditions required to meettreatment efficacy criteria. This system is designed to flood the wastewith chlorine dioxide solution, and steam, if desired, agitating it toallow total waste contact and allow for dilution and complete treatmentof typical concentrations (tested at 5% w/w) of organic materials suchas bulk blood, blood products, and laboratory cultures. Under theseconditions, residual chlorine dioxide levels exceed 300 ppm aftertreatment.

The turbulent forces of the treatment process present no physicallimitation to the types of medical waste that can be treated by the unitunlike the damage that can occur to shredders or hammermills by a smallstainless steel object. The interior of the unit is constructed ofmaterials that can withstand the impact of hard, dense objects. Nomechanical breakdown or compromise of the treatment process is foreseen.

Although chemicals are not considered part of a medical waste load,small amounts may somehow enter the waste stream. No incompatibilitieswith small trace amounts of the typical chemicals (i.e., alcohols,formaldehyde, glutaraldehyde) that might be associated with medicalwastes are envisioned. No mechanical breakdown or compromise of thetreatment process is foreseen.

Microbiological Testing Procedures

Efficacy tests were conducted with B. stearothermophilus spores(indicator strips containing in excess of 6 Log₁₀ of spores) todemonstrate microbial effectiveness of the Unit. Spores strips wereremoved from their protective envelopes, wrapped in a nylon material,placed into perforated screw-capped polypropylene tubes, and attached tothe inside of the treatment chamber of the Unit prior to waste loading.Upon completion of the treatment cycle and neutralization cycles, thetubes were removed from the unit for off-site quantitative/qualitativeanalysis. The method of introduction of the spores to the treatmentprocess was chosen to both retrieve intact spore strips yet subject themto the same physical conditions that waste would receive during theprocess.

Note that B. stearothermophilus is now referred to as Geobacillusstearothermophilus. For the purposes of this discussion, B.stearothermophilus will be the terminology used in this report.

By-Products and Discharges of the Treatment Process

As with any medical waste treatment methodology that employs chemicalprocess to treat medical waste, certain by-products are expected to begenerated from that process. For the Unit, these bi-products includepotential bioaerosols, gaseous chlorine dioxide, chlorine dioxidetreatment solution, and waste residue. To control and mitigate thesebi-products to protect from occupational exposures or environmentalreleases, every effort has been taken to “engineer out” these potentialexposures or releases during both routine and unscheduled operationsthrough the incorporation of monitoring and control devices throughoutUnit. These monitoring and control devices are summarized below.

Biological Aerosols

The Unit has been designed as a batch-process system that minimizes orprecludes bio-aerosols from forming or being released prior to or duringprocessing. Medical waste is placed directly into the treatment chambervia an automated tipper or manually and once the chamber is filled, thehydraulic door is automatically closed and sealed for operation. Thewaste remains intact as the chamber is filled to the proper amount andconcentration of the chlorine dioxide solution and once filled, thechamber initiates its rotational sequence to create turbulent conditionsthat subject the entire content of the waste load to the biocide. Duringthe process some pressure is created releasing small concentrations andamounts of any volatilized chlorine dioxide to the chamber's ventingsystem. An activated carbon filter may be entrained in the ventilationduct to trap any fugitive emissions. The vented chlorine dioxideinactivates bio-aerosols that might escape via this route. Any chlorinedioxide that may escape to the atmosphere will be quickly inactivated bysunlight.

Liquid Treatment Solution

No residual chlorine dioxide will be discharged to the sanitary sewersystem, although chlorite will be formed as from the waste-chlorinedioxide interaction. The Unit utilizes a chlorine dioxide solution thatis applied to the waste to provide microbial inactivation. Duringtreatment chlorite ions are formed as chlorine dioxide is used up indisinfection reactions. Upon completion of the treatment process, anyremaining chlorine dioxide is neutralized using either a sodium orpotassium sulfite solution to form either sodium or potassium sulfite.Using sodium sulfite as the neutralizing agent example, the reactionproceeds as follows: 5Na₂SO₃+2ClO₂+H₂O→5Na₂SO₄+2HCl. Chlorite will reactwith the neutralization agent, although somewhat more slowly, but as thewastewater mixes with other water and the pH is reduced, the reactionwill speed up. In addition, the presence of sulfides in the municipalsewer system will rapidly consume any chlorite that remains.

Chemical Emissions

The Unit utilizes chlorine dioxide to inactivate infectious agents thatmight be present in medical wastes. Chlorine dioxide is generated via achlorine dioxide generator developed and patented by Dr. Greg D.Simpson. U.S. Pat. No. 6,171,558 issued Jan. 9, 2001 to Greg D. Simpsonis hereby incorporated by reference in its entirety. This generator canuse either the precursors of (1) chlorine gas and aqueous sodiumchlorite or (2) sodium hypochlorite, hydrochloric acid, and sodiumchlorite.

Chlorine dioxide is a strong oxidizer and as such, may cause irritationto the skin and redness and irritation to the eyes. Chlorine dioxide isharmful if inhaled with an assigned Permissible Exposure Level TimeWeighted Average of 0.1 ppm and Threshold Limit Value TWA of 0.1 ppm.The Unit has been designed to prevent operator exposure to chlorinedioxide through a self-contained process in which chlorine dioxidesolution is generated, applied to the waste, neutralized, and dischargedto the sanitary sewer. The treatment chamber is watertight duringoperation. During the process some pressure is created releasing smallconcentrations and amounts of any volatilized chlorine dioxide to thechamber's venting system. An activated carbon filter may be entrained inthe ventilation duct to trap any fugitive emissions.

The Unit has been designed with both automatic and manual shutdown modesthat are or can be activated in the event of a malfunction or emergencyevent to preclude the release of chemical agents. The unit has beenadditionally designed to be self-contained so that in the event of amalfunction or unplanned event, no or negligible chemical releases tothe environment will occur.

Odors

A deodorization system (HEPA filter) may be used to deodorize any vaporsor gasses that may be emitted from the unit via the unit's ventilationsystem. Any chlorine dioxide that may be released to the atmosphere willhave a very limited lifespan since it decomposes within minutes in thepresence of sunlight. Processed waste will contain no chlorine dioxide(the only source of odor in this system) since the chlorine dioxide isneutralized prior to the waste's automatic removal from the Unit. Thewaste material itself will be deodorized by the normal action of thechlorine dioxide, which is a deodorizer.

Treated Waste Residue

The Unit generates a waste residue that is comprised of macerated wastematerials that are microbiologically inert after treatment. The wastewill retain some moisture from the chlorine dioxidetreatment/neutralizing solutions. However, the amount of liquid/moistureretained is minimal since the treated waste is subjected to dewateringvia a high velocity spin cycle at the end of the neutralization cycle.Preferably, the spin cycle generates centrifugal forces sufficient toremove most of the liquid in the residual waste. For example, the Unitis designed to provide a spin cycle that generates centrifugal forces ofup to about 300 g. Chlorine dioxide in the waste will be neutralizedprior to waste discharge. The treated waste residue would be deemednon-infectious and would be classified as a general solid wasteacceptable for landfill disposal.

Environmental Effects of the Treatment Process

The Unit medical waste treatment processor utilizes high waterturbulence and internal cutting blades to break open waste containersand expose the waste to chlorine dioxide solution to inactivatemicroorganisms. Prior to discharge of the chlorine dioxide solution andthe treated waste, remaining chlorine dioxide is “neutralized” witheither sodium or potassium sulfite resulting in no discharge of chlorinedioxide to the sanitary sewer or to the landfill. The chemical reaction(sodium sulfite) is as follows: 5Na₂SO₃+2ClO₂+H₂O→5Na₂SO₄+2HCl. Duringtreatment chlorite ions are formed as chlorine dioxide is used up indisinfection reactions. Chlorite will react with the neutralizationagent, although somewhat more slowly, but as the wastewater mixes withother water and the pH is reduced, the reaction will speed up. Inaddition, the presence of sulfides in the municipal sewer system willrapidly consume any chlorite that remains. No negative effects areanticipated on the environment from the use or disposal of treated wastefrom the Unit. The treatment solution and treated medical waste isneutralized prior to its discharge from the unit resulting in nonegative chemical discharges to the sewer or landfill.

The Unit has been designed with both automatic and manual shut-downmodes that are or can be activated in the event of a malfunction,emergency or unplanned event to preclude the release of chemical orbiological agents. The unit has been additionally designed to beself-contained so that in the event of a malfunction or unplanned event,no or negligible chemical or biological releases to the environmentwould occur.

The Unit generates a waste residue that is comprised of ruptured andmacerated materials that are microbiologically inert after treatment.The waste will retain minor amounts of moisture from the neutralizedchlorine dioxide treatment solution. The amount of moisture will beminimal due to the dewatering affect of the high-speed final spin cyclethat generates in excess of 300 g to the waste load. The treated wasteresidue would be deemed non-infectious and would be classified as ageneral solid waste acceptable for landfill disposal. The waste residuewill be disposed as a general solid waste in a solid waste landfill.There are no by-products identified as a hazardous waste as a result ofthis treatment process.

Occupational Hazards

As with any medical waste treatment methodology that employs a chemicaltreatment process to treat medical waste, potential occupational hazardscan exist in the operation of such a unit and with the handling ofmedical waste destined for treatment in the unit. As such, potentialexposures to occupational hazards may include exposures to electrical,mechanical/physical, chemical, and biological sources associated withthe operation of the Unit. Every effort has been taken to “engineer out”these potential exposures during both routine and unscheduledoperations. Additionally, the use of personal protective equipment isalso prescribed and integrated with appropriate training where and whennecessitated.

The Unit was designed with safety being of foremost concern. Everypossible effort has been made to incorporate features into the systemthat guard against potential electrical, mechanical, chemical, andbiological hazards. The unit has also been equipped with a series ofprotective devices, termed “interlocks”, which have been designed toadditionally protect personnel when internal maintenance or repair isperformed. The safety features incorporated into the Unit are summarizedbelow.

Electrical

As with any high voltage equipment like the Unit, there are inherentelectrical dangers that must be recognized by all personnel operatingand maintaining/repairing the unit. Primary in electrical safety is theinstitution and implementation of “Lockout-Tagout” procedures. Theseprocedures and related design characteristics of the unit have beendeveloped to purposely disable the unit when personnel might be atincreased risk of injury due to internal repair, maintenance,troubleshooting or when accessing the “Master Control Center.”

During waste processing, there is an “Emergency Master Switch” that willde-energize every sub-system of the Unit. The emergency master switch islocated on the Master Control Board. The emergency switch is designedfor life threatening situations only. All wiring and switches on theunit are enclosed and meet UL standards. Any activities involving anyelectrical circuitry are only to be performed by a competent electricianknowledgeable of the unit's electrical circuitry.

Mechanical

The Unit has been designed to limit exposure to any moving parts. Movingparts on the Unit include the hydraulic door, hydraulic lift for thetreatment chamber, the optional hydraulic tipper, and the treatmentchamber's belt drive. During the any hydraulic lift operation, theclosing of the door and the activation of the chamber lift, both audibleand visible alarms are activated to alert the operator and others of thepotential danger for the movement of these parts. The treatmentchamber's belt drive is completely enclosed and cannot be accessedduring the unit's operation.

Chemical

The Unit utilizes chlorine dioxide to inactivate infectious agents thatmight be present in medical wastes. Chlorine dioxide is generated via achlorine dioxide generator developed and patented by Dr. Greg D.Simpson. This generator can use either the precursors of (1) chlorinegas and aqueous sodium chlorite or (2) sodium hypochlorite, hydrochloricacid, and sodium chlorite. The system is totally enclosed. As thechlorine dioxide generator operates and fills the unit based on vacuumeduction, any leaks in tubing or other components will result in airinduction, and not the leaking of precursors. No contact of personnelwith chlorine dioxide or its precursors will occur at any time duringthe process. The creation and use of the chlorine dioxide will beautomatic, as will the neutralization step at the end of the process.Procedures have been developed for the storage of all chemicals requiredfor the generation of chlorine dioxide and its neutralization. Theprocess can be activated or accelerated by the use of heat, for example,in the form of superheated water or steam. Although this is not requiredfor treatment, it is expected it would be useful to speed up the processtime or if additional treatment is required for particular types ofinfectious material.

Biological

The Unit has been designed as a batch-process system that minimizes orprecludes bio-aerosols from forming or being released prior to or duringprocessing. Medical waste is placed directly into the treatment chambervia an automated tipper or manually and once the chamber is filled, thehydraulic door is automatically closed and sealed for operation. Thewaste remains intact as the chamber is filled to the proper amount andconcentration of the chlorine dioxide solution and once filled, thechamber initiates its rotational sequence to create turbulent conditionsthat subject the entire content of the waste load to the biocide. Duringthe process some pressure is created releasing small concentrations andamounts of any volatilized chlorine dioxide to the chamber's ventingsystem. An activated carbon filter may be entrained in the ventilationduct to trap any fugitive emissions. The vented chlorine dioxideinactivates bio-aerosols that might escape via this route. Any chlorinedioxide that may escape to the atmosphere will be quickly inactivated bysunlight.

All personnel involved with the operations and maintenance of the Unitwill receive training to ensure proper and safe operation of the unitand to ensure the safe handing and disposal of the medical waste treatedby the unit. Training will also be conducted on the proper personalprotective equipment requirements, chemical storage requirements,chemical use, spill control and containment (chemical and biological),and emergency response (chemical and biological). No one will be allowedto operate, maintain, or repair the unit without proper training orsupervision.

All personnel involved with any operation of the Unit will be requiredto be knowledgeable of the operational and safety processes/procedures.

Critical Factors of the Treatment Process

The critical factor of the treatment process is the amount of organicmaterials in the medical waste stream and its influence on the chlorinedioxide concentration in the treatment solution. The Unit has beendesigned and demonstrated to effectively treat a composite medical wastestream consisting of bulk blood, blood products, body fluids,microbiological wastes, sharps waste, and isolation wastes. Waste loadscontaining excessive amounts of high organic-containing wastes fromanimals including bedding and carcasses have not been tested todetermine treatment conditions required to meet treatment efficacycriteria.

Adverse environmental or occupational effects are also not anticipatedin the event of an unanticipated large volume of organic materialentering the Unit for treatment. The treatment efficacy results underthe established processing times and chlorine dioxide concentrationsexceed those criteria recommended in “Technical Assistance Manual: StateRegulatory Oversight of Medical Waste Treatment Technologies” and theLog reductions acquired in these tests were limited by the initialchallenge organism concentrations that could be obtained for the studies(e g, limited to a 6 Log₁₀ spore concentration per test strip).Additionally, the concentrations of challenge microorganisms processedin these studies would exceed those pathogen concentrations typicallyencountered in a medical waste stream. However to ensure that effectivetreatment is occurring, biological monitoring will be performedroutinely using spore strips containing 1×10⁴ spores of B.stearothermophilus. It should also be noted that no occupational contactoccurs with the waste or waste residue after the medical waste bag/boxis loaded into the unit until the time of automatic discharge into awaste container after all cycles have been completed.

The Unit has been designed to be operator “friendly” through acomputer-controlled operating system which provides real timeinformation and operator direction via a visual display on the MasterControl Center panel. Intrinsic to the computer-controlled operatingsystem are the process sensors that monitor the Unit to ensure safe andeffective operation. These sensors are designed to detect abnormalitiesthat may affect proper waste treatment or unit damage by issuing anoperator warning and/or initiating auto shutdown of the entire wastetreatment process. The Unit can be safely operated by one individual.

As with any highly mechanized system, routine periodic maintenanceschedules are required to ensure that all operating systems will performas specified without unscheduled interruptions. Routine visualinspections will also occur prior to and during the unit's operation toensure that all functions not under computer control are operating asspecified. These inspections would include a survey of floor areasaround and under the unit to check for leaks (i.e., water, treatmentsolution, lubricating fluids). Additionally the unit would be inspectedfor any signs of unusual wear of belts or other moving parts. Any repairor any internal inspections will be performed under “Lockout-Tagout”conditions to ensure personnel safety from electrical and physical harm.Properly trained individuals will perform all operations, repair, andmaintenance.

The chlorine dioxide generator is virtually maintenance-free. Periodicreplacement of 25% sodium chlorite, chlorine (or acid and bleach) andneutralization solution will be required, probably on a once a month toonce every 2 month basis.

In the event of a critical malfunction, the Unit has both automatic(computer-recognized and controlled) and operator-controlled emergencyshutdown mechanisms. Automatic-controlled emergency mechanisms areinitiated by sensors located in strategic control points within the unitand would send an alarm to the computer or operator to initiate autoshutdown procedures. An Emergency Master Switch is also available toinitiate immediate and complete shutdown of the unit by the operator ifcircumstances require. In the event of a malfunction, the unit has beendesigned to be self-contained to avoid release of chemical or biologicalcontaminants to the area.

The Unit has a fixed treatment cycle time of six minutes to provideadequate chlorine dioxide solution contact time. The addition of thechlorine dioxide solution to the waste load requires approximately fourminutes and the neutralization rinse cycle requires approximately twomore minutes. With loading and unloading the waste, total turnaroundtime for a waste load is approximately 20-25 minutes.

Chemical Inactivation Treatment Processes

Chlorine dioxide is the preferred germicidal agent used in the Unit totreat medical waste. Chlorine dioxide can be generated by (1) combininghydrochloric acid with sodium hypochlorite to form chlorine which issubsequently reacted with sodium chlorite or by (2) combining chlorinegas with sodium chlorite. Sodium chlorite is the preferred precursorchemical for use in a medical waste processor or processing method.

The preferred concentration of chlorine dioxide used to inactivatemicroorganisms is 350 ppm in aqueous solution.

The pH of the treatment solution has little effect on the germicidalactivity of chlorine dioxide. Unlike chlorine, chlorine dioxide does nothydrolyze in water and therefore its germicidal activity is relativelyconstant over a broad pH range. Chlorine dioxide retains its biocidalactivity over a pH range of 4-10.

Six minutes has been established as the sufficient processing or contacttime through the Unit, although the time may vary depending on themechanical agitation of the chamber, the physical nature of the medicalwaste, the particular infectious hazard or hazards in the medical wasteto be treated, etc. Should enhanced or shorter time periods fortreatment be desired, the introduction of superheated water or lowpressure steam can accelerate the treatment process.

The materials of compatibility of chlorine dioxide are well known.Chlorine dioxide is a powerful oxidizing agent and as such will reactwith reducing agents, oxidizable organic dusts, phosphorous, potassiumhydroxide, sulfur, mercuric fluoride, difluoroamine, carbon monoxide,natural rubber seals, carbon steel, copper containing metallurgies, andmercury. The generator has been designed so that all surfaces that theprecursors or chlorine dioxide solution contacts is compatible. Littleor no apparatus surface corrosion or incompatibility from chlorinedioxide solution is expected during the operative life of the Unit.Hydrochloric acid should always be stored away from the other twoprecursor chemicals (sodium hypochlorite and sodium chlorite) to avoid apotential dangerous release of chlorine gas or chlorine dioxide if thesechemicals were accidentally mixed. Both sodium hypochlorite and sodiumchlorite can also be dangerous if allowed to come into contact withreducing agents or flammable materials and as such, require appropriatestorage away from these chemicals. Sodium chlorite can also becomehazardous if allowed to come into contact with simple organic materialssuch as wood pallets, rags, etc. In the event of a leak or spill, apotentially flammable powder can result after water evaporation. Thismaterial can be self-igniting if exposed to any source of friction, butcan remedied by immediately flushing any spill with excessive amounts ofwater.

The pH of the spent treatment solution is typically expected to be inthe range of pH 7 to 9.

The only way that chlorine dioxide could be ineffective is thatsomething is in the water or waste that reacts more rapidly withchlorine dioxide than the chlorine dioxide can react with bacteria. Asmost of the bacterial activity occurs within the first minute ofcontact, the only chemical species that could react more rapidly wouldbe some kind of reduced sulfur compound, such as sulfite (the solutionused to neutralize the chlorine dioxide solution), or H₂S, or sulfide,or any other reduced sulfur compound.

The active life of chlorine dioxide is subject to its rate ofdecomposition. Although stable under ambient conditions, chlorinedioxide is generated on-site as a liquid just prior to its use to ensureits proper treatment concentration. In the Unit and medical wastetreatment process, chlorine dioxide is generated on a per cycle basis tothe intended treatment concentration specified to ensure microbial kill.The neutralizing solution will inactivate chlorine dioxide within a fewseconds. There is not expected to be any chlorine dioxide remaining inthe medical waste after it has been inactivated. In the environmentchlorine dioxide in solution is light sensitive. It reacts with light togenerate other free radicals (ClO⁻ and O⁻) react via a variety of otherpathways to form Cl₂, chlorine dioxide⁻, ClO₃ ⁻, and Cl⁻. Thedecomposition rate of chlorine dioxide solution depends on many factorssuch as temperature and extreme pH.

There are numerous studies on the long-term effectiveness during use.Chlorine dioxide was used as the bio-terrorism remediation of theanthrax spore release in Washington D.C. in 2001-2002 and is usedextensively by laboratory personnel to inactivate the SARS virus in EastAsia. Its use as an effective germicide agent is well studied anddocumented.

Chlorine dioxide is an oxidizing agent and as such, the primary healthconcern is the oxidative effect that chlorine dioxide may have on bodytissues and the blood. Exposures to eyes and skin may cause irritation.The chemical is harmful if swallowed and may be poisonous if inhaled. Noeffects of carcinogenicity have been reported. OSHA eight-hourtime-weighted average Permissible Exposure Limit for “ambient chlorineand chlorine dioxide gas are 1.0 ppm and 0.1 ppm, respectively. Theconcentrations of chlorine and chlorine dioxide gas considered to beImmediately Dangerous to Life and Health by NIOSH are 30 ppm and 10 ppm,respectively. None of these “breathing zone” standards should ever beexceeded in the workroom area under normal Unit operating conditions.Chlorine dioxide has the potential to become explosive when mixed withair at partial pressure above 80 mm Hg. The intrinsic design of thechlorine dioxide generator used in the Unit will not allow thiscondition to develop. For additional health and safety information onchlorine dioxide, its precursor chemicals, and neutralization chemicals,refer to Material Data Safety Sheets. It should be emphasized that inthe Unit and for the processing system that chlorine dioxide is inaqueous solution and is safe. Chlorine dioxide is used to purifydrinking water and chlorite (decomposition product) is used in wounddressings and toothpaste as an antibacterial at concentrations of 1000ppm.

The active ingredient for the production of chlorine dioxide is sodiumchlorite.

Quality Assurance and Verification of Adequate Treatment

The efficacy of the treatment process is a function of chlorine dioxidesolution concentration and time of contact. As such, the generation ofthe chlorine dioxide to the appropriate concentration and deliveryvolume is critical to the treatment process. The chlorine dioxidesolution will be monitored during its generation to insure that aminimum level of chlorine dioxide is delivered to the waste in bothconcentration and volume. The Unit is also pre-programmed to ensure atreatment (chlorine dioxide contact) cycle is maintained for theduration required for microbial kill. It is expected that under typicalconditions for the Unit, about six minutes should be sufficient.Verification of the chemical concentration determined by directmonitoring will be conducted weekly against a standard titrationprocedure to insure that the instrument remains in calibration. Alsoweekly, biological spore strip testing will be conducted to correlatebiologically that the chemical concentration and contact time issufficient to effect microbial kill.

Periodic user verification (periodic biological inactivation monitoring)will employ the use of spore strips containing 1×10⁴ spores of B.stearothermophilus. Multiple spore strips will be placed within aprotective sheath located on one of the cutting blades to monitor thewaste treatment efficacy. The spore strips are subsequently processedalong with the waste and are retrieved manually from chamber upondischarge of the waste from the unit. Upon retrieval, the spore stripsare placed into nutrient media and incubated at 55-60° C. for 48 hours.Growth (demonstrating treatment process inadequacy) is determined byculture media turbidity. If growth occurs in more than one sample, thetreatment process and other parametric controls shall be reviewed andthe biological indicator test shall be repeated accordingly. If thesecond test also reveals insufficient microbial inactivation, the unit'suse shall be discontinued until the problem is discovered and corrected.

Integral to the chlorine dioxide generation process, is water flow andwater pressure that is also monitored to ensure the proper concentrationand volumes of solution are delivered to the unit.

The total waste processing system is under microprocessor control toensure all cycles and their durations are completed with the appropriateamounts of solutions at the proper concentrations. Continuous chlorinedioxide process monitoring will ensure that the proper amounts andconcentrations will be delivered to the waste being processed.Independent verification of those processes will be performed weekly toensure effective microbial kill using biological spore strips.

Treatment efficacy studies have been conducted to correlate the contacttime and chlorine dioxide concentration conditions against the efficacyof killing bacterial spore populations. The conditions found to beeffective in killing greater than 6 Log₁₀ spore populations are thoseused as standard operation conditions. (See attached treatment efficacyreport.)

Monthly, the chlorine dioxide concentration that is monitoredinstrumentally will be checked against a standard titration procedure toinsure that the instrument remains in calibration.

Process monitors have been set to ensure that unless the minimumconcentration of chlorine dioxide is applied, the unit will not run.

The unit is pre-programmed to operate at the conditions set by thefactory and cannot be overridden by the operator. Additionally the unitwill be electronically linked to the corporate office where allfunctions and operations can be monitored by corporate staff foroperational oversight to a unit's performance and as a method ofdiagnosis for any potential equipment condition(s) that may lead toequipment failure or inadequate waste treatment.

Post-Treatment Residue Disposal, Reclamation or Recycling

Treated waste residues will be placed in dedicated containers fordisposal as a general, solid waste in municipal landfills.

It is to be understood that the various steps according to preferredelements of the apparatus and steps of the methods of the invention canbe advantageously practiced in various combinations.

Thus, the present invention is well adapted to carry out the objects andattain the ends and advantages mentioned above as well as those inherenttherein. While preferred embodiments of the invention have beendescribed for the purpose of this disclosure, changes in theconstruction and arrangement of parts and the performance of steps canbe made by those skilled in the art, which changes are encompassedwithin the spirit of this invention as defined by the appended claims.

1-70. (canceled)
 71. A method of treating medical waste with anapparatus, (A) wherein the apparatus comprises: (i) a drum defining asubstantially cylindrical treatment chamber having a closed end and asubstantially open end, wherein the drum is rotationally balanced abouta rotational axis; (ii) an enclosing body supporting the drum so thatthe drum can be rotated within the body about the rotational axis of thedrum, the body having an opening for accessing the open end of the drum,wherein the opening is located substantially in a plane perpendicular tothe rotational axis of the drum; (iii) a movable barrier for selectivelyclosing the opening for accessing the open end of the drum; (iv) astructure for supporting the enclosing body so that the pitch of therotational axis of the drum is positioned or can be positioned in atleast one position between about 0 degrees and about 30 degrees; and(iv) a movable mounting for the enclosing body operatively positionedbetween the enclosing body and the structure for supporting theenclosing body such that the pitch of the rotational axis of the drumcan be selectively moved; and (B) wherein the method comprises the stepsof: (i) moving the enclosing body such that the pitch of the rotationalaxis of the drum is between about 10 degrees and about 30 degrees andsuch that the opening is oriented at least partially upward tofacilitate loading of medical waste at least partially downward into thetreatment chamber; (ii) loading medical waste through the opening intothe treatment chamber; (iii) positioning the movable barrier to closethe opening; (iv) moving the enclosing body such that pitch of therotational axis of the drum is between about 0 degrees and about 10degrees; (v) introducing into the treatment chamber a germicidal agent;and (vi) rotating the drum to agitate the medical waste with thegermicidal agent.
 72. The method according to claim 71, wherein the stepof loading medical waste into the treatment chamber further comprises:pouring the medical waste from a bin through the upwardly orientedopening for accessing the open end of the drum and into the treatmentchamber.
 73. The method according to claim 71, wherein the step ofloading further comprises: rotating the drum about the rotational axisof the drum so that the treated medical waste is rotated upward on aninner wall of the drum and then tumbles by gravity farther down into thetreatment chamber of the drum.
 74. The method according to claim 73,wherein the step of loading further comprises: rotating the drum atleast one-half of a revolution about the rotational axis in onerotational direction and rotating the drum at least one-half arevolution about the rotational axis in the opposite rotationaldirection.
 75. The method according to claim 71, wherein the step ofmoving the enclosing body such that the pitch of the rotational axis ofthe drum is between about 0 degrees and about 10 degrees furthercomprises: moving the enclosing body such that the pitch of therotational axis of the drum is substantially 0 degrees.
 76. The methodaccording to claim 71, the method further comprising the steps of: (vii)moving the movable barrier to reopen the opening; and (viii) moving theenclosing body such that the pitch of the rotational axis of the drum isbetween about 10 and about 30 degrees and such that the opening isoriented at least partially downward to facilitate unloading of medicalwaste at least partially downward from the treatment chamber; and (ix)unloading the treated medical waste from the treatment chamber.
 77. Themethod according to claim 76, wherein the step of unloading furthercomprises: rotating the drum about the rotational axis of the drum sothat the treated medical waste is rotated upward on an inner wall of thedrum and then tumbles by gravity out of the open end of the treatmentchamber of the drum and to the outside of a lower edge of the opening inthe enclosing body.
 78. The method according to claim 77, wherein thestep of unloading further comprises: rotating the drum at least one-halfof a revolution about the rotational axis in one rotational directionand rotating the drum at least one-half a revolution about therotational axis in the opposite rotational direction.
 79. The methodaccording to claim 71, further comprising the step of: collecting themedical waste into a bin for transport to the apparatus.
 80. The methodaccording to claim 76, wherein the step of unloading further comprising:unloading the medical waste that has been treated in the apparatus intoa bin for transport to a non-medical waste collection area for disposalas non-medical waste.
 81. The method according to claim 71, wherein theapparatus further comprises: a plurality of rotationally-balanced bladespositioned inside the drum, whereby when the drum is rotated, thetumbling of the medical waste in the treatment chamber onto the bladesruptures containers and bags of the medical waste.
 82. The methodaccording to claim 81, wherein the blades are positioned on an insidewall of the drum.
 83. The method according to claim 81, wherein theblades are adapted to rupture disposal containers for needles orsyringes that may be present in the medical waste when the drum rotatesat a speed to tumble the medical waste in the treatment chamber.
 84. Themethod according to claim 71, wherein the enclosing body is fluid-tight,the movable barrier is fluid-tight, and wherein the apparatus furthercomprises: a fluid-tight seal operatively positioned between theenclosing body and the removable barrier, whereby the enclosing body isfluid tight when the movable barrier closes the opening for accessingthe open end of the drum.
 85. The method according to claim 84, whereinthe wherein the apparatus further comprises: a vent to the atmosphere.86. The method according to claim 85, wherein the vent is closed whilegermicidal agent is introduced into the treatment chamber.
 87. Themethod according to claim 71, wherein the step of introducing into thetreatment chamber a germicidal agent further comprises the step of:introducing a germicidal agent having at least a sufficienteffectiveness in at least a sufficient concentration under conditions atleast sufficient to achieve “Level W Microbial Inactivation.”
 88. Themethod according to claim 71, wherein the germicidal agent compriseschlorine dioxide.
 89. The method according to claim 71, furthercomprising the step of: heating the medical waste in the treatmentchamber.
 90. The method according to claim 89, wherein the step ofheating the medical waste further comprises: introducing superheatedwater or steam into the treatment chamber.
 91. The method according toclaim 71, further comprising the step of: after the step of agitatingthe medical waste with the germicidal agent in the treatment chamber;neutralizing any residual germicidal agent with a neutralizing fluid.92. The method according to claim 91, wherein the germicidal agentcomprises chlorine dioxide and the neutralizing fluid comprises asulfite.
 93. The method according to claim 71, further comprising thestep of: recycling germicidal agent for use in a subsequent treatment ofanother batch of medical waste. 94-99. (canceled)